Fixes/improvements to the signature and hash wrappers:

Fixed output buffer to wc_RsaSSL_Verify so its min size is the key size (needed for inline operations).
Fixed the signature wrapper return codes when using RSA so 0 indicates success.
Fixed signature wrappers use of wc_HashGetDigestSize to return the error code result.
Changed enum wc_HashType and enum wc_SignatureType so all values always exist.
Added new "wc_HashGetOID" which returns the OID for an enum wc_HashType.
Added new "WC_SIGNATURE_TYPE_RSA_W_ENC", that adds the encoded ASN header to the digest using wc_EncodeSignature for RSA signatures.
Added new SIG_TYPE_E and HASH_TYPE_E error types for explicit reporting of sig/hash type not available.

wolfcrypt/src/error.c

@@ -367,6 +367,12 @@ const char* wc_GetErrorString(int error)
     case BAD_COND_E:
         return "Bad condition variable operation error";
 
+    case SIG_TYPE_E:
+        return "Signature type not enabled/available";
+
+    case HASH_TYPE_E:
+        return "Hash type not enabled/available";
+
     default:
         return "unknown error number";